Abstract
Purpose :
Trabecular bypass stents (TBS) are implanted through the human trabecular meshwork (HTM) to improve physiologic outflow and lower intraocular pressure in open-angle glaucoma. Given the widespread use of TBS, improved understanding of their biocompatibility is imperative. Of the two commercially available TBS, one is comprised of titanium & the other of nickel-titanium (nitinol). This study tested the hypothesis that there would be differences in the viability of primary HTM cells in culture when contacted with one versus the other of these devices.
Methods :
HTM cells were grown on glass or gelatin-coated glass substrates & then placed into contact with sterile stents. Cell morphology in the vicinity of the stents was monitored every day for 4 days via optical microscopy, and live-dead fluorescence staining was performed to assess cell viability. The corrected total fluorescence of micrographs imaged under identical conditions (N≥21 per timepoint) was quantitated w/ ImageJ software. Data were analyzed using two-way ANOVA & compared to stent-free samples w/ Tukey’s multiple comparison test.
Results :
Cells cultured in contact with nitinol stents for 48, 72 & 96 hours demonstrated progressive cell necrosis, clumping, and in some cases, complete cell layer detachment. However, cells in contact with titanium stents remained attached to the substrate & showed little or no necrosis. Dead-cell staining intensity was greater after nitinol vs. titanium stent contact (p<0.0001, N=21/stent) across all timepoints examined.
Conclusions :
HTM cells remained viable & morphologically intact when in contact with titanium stents, whereas contact with nitinol stents led to necrosis & morphological degradation. These differences were statistically significant & visually apparent.
This is a 2021 ARVO Annual Meeting abstract.